Diagnosis and treatment of vascular conditions are commonly performed using percutaneous vascular procedures, which may involve the insertion of a catheter or the like into a blood vessel, artery, or other passageway of the vascular system. For example, known catheterization procedures include the positioning and use of stents and balloons within constricted vessels or arteries, and the intravenous administration of bloods, drugs, and other fluids. The first step in the performance of these procedures is the establishment of a site through the skin by which access is made to the blood vessel or artery. A wire guide is then introduced into the vessel or artery and advanced to a desired location, often with the assistance of a guide catheter. A working catheter may then be advanced to the desired location over the wire guide in a safe and atraumatic fashion.
Conventional wire guides must exhibit flexibility in order to successfully navigate the tortuous passages of the vascular system, but also must have a certain amount of stiffness to pass through lesions and support other medical devices that are subsequently introduced over the wire guide. Thus, conventional wire guides, regardless of the particular application, are typically subject to conflicting requirements. Further, depending on the particular application, certain portions of the passageway being navigated may require a wire guide that is stiffer than some standard conventional wire guides, whereas other portions of the passageway may require a wire guide that is substantially more flexible than standard wire guides. As a result, a clinician may need to introduce multiple wire guides having different properties during a single procedure.
For example, during an exemplary percutaneous vascular procedure, the clinician may begin with a relatively stiff wire guide to gain access through the passageway. As the passageway becomes smaller and more tortuous, the clinician may need to replace the stiffer wire guide with a more flexible wire guide. This may be accomplished by passing a catheter over the first wire guide until the distal end of the catheter reaches the distal end of the wire guide. The first wire guide is then withdrawn from the catheter and the second wire guide is introduced through the catheter. The second, more flexible wire guide may then be advanced beyond the distal end of the catheter and through the more tortuous section of the vessel. If a lesion, or occlusion, is encountered that is difficult to pass using the second wire guide, the catheter may be advanced to increase the stiffness at the distal tip of the second wire guide. Alternatively, however, it may be desirable to replace the second wire guide with a third, relatively stiff wire guide. This need to exchange wire guides during the procedure adds to the complexity, duration, and cost of the procedure. In addition, exchanging one wire guide for another may increase the risk of contamination, and potential infection, to the patient.
The present disclosure is directed toward one or more of the problems set forth above.